Joggling is the process of deforming a plate-shaped member by bending the member along two parallel spaced axes through equal and opposite angles. The resulting deformation is referred to as a joggle. Joggles permit flush connections to be made between two plates, sheets, or structural members. In many applications, it is desired to form joggles in L-shaped or T-shaped members having a cap portion that is to be joggled and a leg portion that is joined to the cap portion at an angle. The usual approach to joggling such workpieces involves clamping the leg of the workpiece between two clamping members so that the leg does not wrinkle during the deformation process. In most joggling presses, two actuators are used for moving the clamping members toward each other to clamp the leg, and a third actuator is used to move a forming die along a direction normal to the direction along which the clamping member is moved so that the forming die engages the cap and deforms it to a desired shape.
Conventional joggling presses typically have forming dies that are specifically configured to form only one workpiece configuration. Commonly, two forming dies are bolted to an upper press member and two cooperating forming dies are mounted to the lower press member for engaging and deforming the cap between the two pairs of forming dies. The two lower forming dies comprise clamping members that are movable toward and away from each other. They are typically supported between a pair of fixed blocks immovably bolted to the lower press member. The workpiece is positioned by an operator so that the leg is between the clamping members. The two actuators controlling the clamping members are operated to move the clamping members toward each other to clamp the leg. Once adequate clamping pressure has been applied to the leg, the press members are moved relatively toward each other to cause the cap to be pressed between the two pairs of forming dies carried by the two press members such that the cap is deformed to a shape generally conforming to the shape of forming surfaces of the dies. The press members are then moved back apart, and the clamping pressure on the leg is released. The operator then manually removes the workpiece from the press.
One drawback of such conventional joggling presses is that when a different workpiece configuration is to be produced, the large and heavy forming dies must be unbolted from the press members and removed, and new forming dies must be placed into the press and bolted to the press members. This operation requires considerable time, and is also awkward and cumbersome because of the size and weight of the forming dies, which consist of massive solid metal blocks. A further drawback is that it can be difficult for the operator to locate the workpiece in precisely the correct location with respect to the forming dies. Yet another drawback is the need for two separate actuators for providing the clamping force and the joggling force.